View of the Argo Mill building at 2517 Riverside Drive in Idaho Springs (Clear Creek County), Colorado. The five-story building is red, and includes a headframe and ore processing facility. The building has large white letters on the top level that read: "Argo Gold Mine & Mill." The building is built flush against the side of the mountain. The mine tunnel and mill were built in 1893, and placed on the National Historic Register by the Department of the Interior in 1977 because of the site's contributions to mining history in Colorado.